1. Field of the Invention
The present invention relates to a printing apparatus which is capable of attaching tab sheets at a predetermined position of a printout printed by executing a print job, a method of controlling the printing apparatus, and a recording medium.
2. Description of the Related Art
Conventionally, there has been proposed a printing apparatus having a function of attaching tab sheets (also referred to as “tabbed sheets”) at a predetermined position of a printout printed by executing a print job. As for tab sheets for use by the above-mentioned type of printing apparatus, a combination of a predetermined number of tab sheets is handled as one set. For example, a combination of five tab sheets is handled as one set. Now, it is assumed that three tab sheets are to be inserted into a printout of one copy printed by execution of a print job. In this case, when printing is carried out by setting one set of the five tab sheets, two excess tab sheets are left after printing a first copy. Then, if a second copy is printed out following the same procedure without discharging the excess tab sheets (two tab sheets in the present example), tab portions of five tab sheets in the second copy are arranged differently from those in the first copy. To solve this problem, there has been proposed a technique in which whenever printing per one copy is completed, excess tab sheets left in a sheet feeder (sheet cassette) are discharged into a discharging section to thereby prevent the tab portion arrangement of a plurality of copies from differing from each other (see e.g. Japanese Patent Laid-Open Publication No. 2002-003063). A method disclosed in Japanese Patent Laid-Open Publication No. 2002-003063 includes discharging sheets subjected to one-sided printing after inverting each printed sheet by an inversion path for inverting i.e. turning over a sheet such that the printed surface of the sheet faces downward (i.e. in a face-down state). This prevents the page order of the discharged sheets from being reversed.
Further, there have conventionally been proposed printing apparatuses of a type which is capable of discharging each sheet such that the printed surface thereof faces upward (i.e. in a face-up state). Since printed sheets are discharged face-up, the user can check contents on each of the discharged sheets without inverting the sheet. In this type of printing apparatus, image data items of a plurality of pages contained in a print job are temporarily stored in a memory, and then the stored image data items are sequentially read out in a descending page order (reverse order) from a final page, for printing. This makes it possible to prevent the page order of the sheets discharged face-up from being reversed.
However, in the case of attaching or inserting tab sheets into sheets discharged face-up as mentioned above, the tab sheets are also fed in the reverse order, and hence tab sheets which should originally be discharged as excess tab sheets are used. Therefore, the user is required to set tab sheets in a sheet feeder after manually removing excess tab sheets in advance by taking the number of tab sheets to be inserted into each set of sheets which are to be printed by executing a print job. The trouble of removing the excess tab sheets is burdensome to the user.